Comprehensive Guide to Antibiotics, Antifungals, Antivirals, and Cancer Therapies

Empiric Therapy

An educated guess, a culture and sensitivity BEFORE starting.

Definitive Therapy

Treatment is based on KNOWN organism.

Prophylactic Therapy

Pre-op, sometimes pre-dental procedures.

Host Factors

Age, Allergy, Kidney and liver function, Pregnancy status, Genetics, Infection site, Immune system strength/comorbidities.

Superinfection

Destruction of protective normal flora by treatment; Secondary infection due to already weakened immune system.

Superbugs

Drug-resistant bacteria, some include: C-diff, MRSA, CRE.

Beta-Lactam Antibiotics

Beta-lactamase inhibitors are combo drugs added to prevent the enzyme's activity.

Penicillins

Includes amoxicillin; 4 types: Natural PCN, PCNase resistant, Aminopenicillins, Extended Spectrum.

Indications for Penicillins

Lots of uses including STAPH, STREP, ENTEROCOCCUS; extended spectrum treats many HAI's.

Mechanism of Action for Penicillins

Interferes with cell wall formation.

Adverse Drug Reactions for Penicillins

GI upset, yeast infection; 1-4% have cross reactivity with cephalosporins.

Drug-Drug Interactions for Penicillins

May decrease effectiveness of birth control pills; May increase action of warfarin.

Cephalosporins

Common prefix: cef- or ceph; same MA as penicillin; broad spectrum.

Adverse Drug Reactions for Cephalosporins

Diarrhea.

Glycopeptides

Example: vancomycin; bactericidal, kills the bacteria.

Mechanism of Action for Glycopeptides

Binds to cell wall causing immediate death.

Considerations for Glycopeptides

Red Man Syndrome; infuse slowly over 60 minutes or more.

Adverse Drug Reactions for Glycopeptides

Ototoxicity, nephrotoxicity, renal failure.

Tetracyclines

Example: tetracycline; broad spectrum; bacteriostatic.

Adverse Drug Reactions for Tetracyclines

Discoloration of permanent teeth, inhibits tooth and skeletal formation of fetus.

Contraindications for Tetracyclines

Allergy, pregnant women, children under 8 years old.

Macrolides

Example: azithromycin; bacteriostatic or bactericidal in high doses.

Adverse Drug Reactions for Macrolides

GI upset, transient hearing loss and vertigo, hepatotoxicity.

Aminoglycosides

Example: gentamicin; bactericidal and broad spectrum.

Adverse Drug Reactions for Aminoglycosides

Nephrotoxicity, ototoxicity, tinnitus, vertigo.

Quinolones

Example: ciprofloxacin; alter bacterial DNA; bactericidal.

Adverse Drug Reactions for Quinolones

Black box warning: ruptured tendons and tendinitis.

Sulfonamides

Example: sulfamethoxazole/trimethoprim; bacteriostatic, broad-spectrum.

Adverse Drug Reactions for Sulfonamides

Skin rash or Steven Johnson syndrome, photosensitivity.

Urinary Tract Antiseptics

Example: nitrofurantoin; broad spectrum, bactericidal or bacteriostatic.

Antimycobacterial drugs

Drugs used to treat TB

Risk factors for TB

Immunocompromised or in institutionalized living

TB testing methods

Skin test, chest-Xray or sputum culture

Latent TB infection

No symptoms (can't infect others)

Active TB infection

Symptoms include night sweats, fevers, productive cough, weight loss

Isoniazid

Bactericidal drug that can be given alone for prophylaxis or in combination for treatment

Isoniazid adverse effects

Can be toxic to liver or cause hepatitis, peripheral neuropathy, visual disturbances

Rifampin

Broad spectrum antibiotic indicated for TB, Legionnaires disease, meningococcal meningitis

Rifampin mechanism of action

Inhibits RNA polymerase, suppresses protein synthesis

Rifampin adverse effects

GI effects, hepatotoxicity, orange/red discoloration of urine, sweat, saliva, and tears

Types of fungal infections

Systemic and integumentary infections

Miconazole

Topical antifungal for athlete's foot and vaginal yeast infections

Acyclovir

Antiviral drug indicated for herpes simplex virus, varicella, and herpes zoster infection

Acyclovir mechanism of action

Inhibits viral replication of DNA

Cancer risk factors

Environment, foods, lifestyle, drugs, occupational, reproductive history, age and sex, genetics

Cancer treatment approaches

Surgery, radiation, chemotherapy, stem cell, gene therapy, immunotherapy

Methotrexate

Antineoplastic that inhibits synthesis of DNA in S phase

Cisplatin

Alkylating drug that forms cross-links between DNA strands

Doxorubicin

Anthracycline cytotoxic antibiotic that distorts normal DNA structure

Tamoxifen

Selective estrogen receptor modulator that blocks estrogen from activating breast cancer cells

Monoclonal antibodies

Recognize and bind to a specific binding site, useful in diagnosing and treating diseases

Interferon Alfa-2A

Proteins that are antiviral, antitumor, and immunomodulating

Venous access ports advantages

Quick access to bloodstream, comfort, decreases risk of leaking

Antiretroviral drug therapy goal

Suppress viral replication and decrease viral load

Zidovudine

NRTI that prevents reverse transcriptase to prevent viral DNA synthesis

Antiretroviral drugs adverse effects

Variable among individuals, including hepatic disease, osteoporosis, lipodystrophy